HOXIE, Ark. (AP) — Arkansas State Police say two people have died and two are injured after two Union Pacific freight trains collided in northeast Arkansas.

Arkansas State Police spokesman Bill Sadler said in a news release that authorities were called to the collision about 3 a.m. Sunday near Hoxie.

Sadler said railroad officials told police both trains were carrying toxic chemical cargo. A large number of Hoxie residents have been evacuated.

Arkansas Department of Emergency Management spokesman Kendell Snyder told the Arkansas Democrat-Gazette (http://bit.ly/1oStTeq ) he doesn't know what the toxic substance is. He also said one engine is on fire and crews are trying to put it out.

Sadler said the dead and injured are believed to be train crew members.

Sadler told the newspaper Union Pacific representatives will lead the investigation.